Cook orzo in a large pot of boiling salted water according to package directions. Two minutes before pasta is done, add peas. Cook until pasta is done and peas are tender.
Drain; pour into a bowl.
Whisk together garlic, basil, salt, pepper, vinegar, olive oil and parsley.
Pour dressing over hot pasta and sprinkle with Parmesan. Toss well to combine and serve immediately.